JP2013187756A - Retention mechanism and image reader - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a retention mechanism and image reader capable of suppressing misregistration of an optical member.SOLUTION: A retention mechanism 50 retaining a mirror 32 extending in a y-axis direction comprises: a retention part 40 for retaining an end part of the mirror 32 on the negative direction side in the y-axis direction; a retention part 42 which retains an end part of the mirror 32 on the positive direction side in the y-axis direction, and includes an opposite part 54b, projection 54c, and adjustment screw 54d; the opposite part 54b which is opposite to a main plane S1 of the mirror 32 at the end part of the mirror 32 on the positive direction side in the y-axis direction; the projection 54c which projects from the opposite part 54b and is in contact with the main plane S1 of the mirror 32; and the adjustment screw 54d which projects from the opposite part 54b, is in contact with the main plane S1 of the mirror 32 and has a configuration in which a projection amount to the opposite part 54b is adjustable.

Description

  The present invention relates to a holding mechanism and an image reading apparatus, and more particularly to a holding mechanism and an image reading apparatus that hold an optical member.

  As an invention related to a conventional general holding mechanism, for example, an image reading device described in Patent Document 1 is known. FIG. 7 is an external perspective view of the holding mechanism 500 of the mirror 502 of the image reading apparatus described in Patent Document 1. FIG.

  The holding mechanism 500 includes holding members 504 and 507, a protrusion 505, and pressing members 506a, 506b, 508a, and 508b.

  The holding member 504 is provided with an opening. One end of the mirror 502 is inserted into the opening of the holding member 504. The holding member 504 includes a protrusion 504a and arms 504c and 504d. The protruding portion 504 a protrudes downward from the holding member 504 and is in contact with the main surface 502 a of the mirror 502. The arms 504c and 504d are configured such that the plate-like member is bent so as to form an L shape. The arm 504d faces the main surface 502a of the mirror 502. The protruding portion 505 protrudes downward in the arm 504d and is in contact with the main surface 502a of the mirror 502. Further, the protruding portion 505 is configured by a screw or the like, and has a configuration capable of adjusting the amount of protrusion from the arm 504d.

  The pressing members 506a and 506b are provided in the opening of the holding member 504 and push the main surface 502b of the mirror 502 upward. Accordingly, the protrusions 504a and 505 are in pressure contact with the main surface 502a of the mirror 502.

  The holding member 507 is provided with an opening. The other end of the mirror 502 is inserted into the opening of the holding member 507. The holding member 507 includes a protrusion 507a. The protruding portion 507 a protrudes downward in the holding member 507 and is in contact with the main surface 502 a of the mirror 502.

  The pressing members 508a and 508b are provided in the opening of the holding member 507 and push the main surface 502b of the mirror 502 upward. As a result, the protruding portion 507 a is in pressure contact with the main surface 502 a of the mirror 502.

  In the holding mechanism 500 configured as described above, the position of the mirror 502 around the axis Ax extending in the longitudinal direction of the mirror 502 can be adjusted by adjusting the protrusion amount of the protrusion 505 from the arm 504d. Is possible.

  However, the holding mechanism 500 described in Patent Document 1 has a problem that the position of the mirror 502 is shifted around the axis Ax. More specifically, the protrusion 505 is provided on the arm 504d. The arm 504d constitutes an L-shaped plate member together with the arm 504c. The L-shaped plate member bent in this manner is relatively easily deformed by an external force because the strength of the bent portion is weak. On the other hand, since the protrusion 504a is a part of the flat holding member 504, it is less likely to be deformed than the arm 504d.

  Therefore, when the holding mechanism 500 receives an external force, the angle formed by the arm 504c and the arm 504d may change, and the position of the protrusion 505 may change. However, since the protrusion 504a is difficult to deform, the position of the protrusion 504a does not change. That is, a deviation occurs in the relative position between the protrusion 505 and the protrusion 504a. As a result, the position of the mirror 502 around the axis Ax may be shifted.

  When the holding mechanism 500 as described above is applied to the image reading apparatus, even if the position of the mirror 502 is adjusted when the image reading apparatus is assembled, the mirror around the axis Ax is caused by vibration or the like during conveyance of the image reading apparatus. There was a possibility that the position of 502 was shifted. In addition to vibration during conveyance, the magnitude of the force with which the pressing members 506a, 506b, 508a, and 508b of the holding mechanism 500 push the mirror 502 varies during document reading, and the mirror 502 around the axis Ax varies. There was a risk that the position of would shift.

JP-A-11-112707

  SUMMARY OF THE INVENTION An object of the present invention is to provide a holding mechanism and an image reading apparatus that can prevent the position of an optical member from shifting.

  A holding mechanism according to an aspect of the present invention is a holding mechanism that holds a plate-like optical element extending in a predetermined direction, and a first holding that holds one end of the optical element in the predetermined direction. And a second holding portion that holds the other end portion of the optical element in the predetermined direction, and the second holding portion includes the optical element at the other end portion of the optical element. A first planar member that opposes one principal surface of the element; a first support that projects from the first planar member and contacts the one principal surface of the optical element; A second support portion that protrudes from one planar member and contacts the one main surface of the optical element, and is configured to be capable of adjusting an amount of projection relative to the first planar member. 2 support parts. It is characterized by the above-mentioned.

  An image reading apparatus according to an aspect of the present invention is an image reading apparatus that reads an original, and is a first unit that slides along the original, and includes a light source that irradiates the original with light and the original that reflects the original. A first unit that includes a first mirror that reflects the reflected light to one side in the sliding direction of the first unit, and a second unit that slides along the document, wherein the first mirror A second mirror that reflects the reflected light in a direction perpendicular to the sliding direction, a third mirror that reflects the light reflected by the second mirror to the other side in the sliding direction, and the third mirror are held. And a second unit including the holding mechanism and an image sensor that receives the light reflected by the third mirror.

  ADVANTAGE OF THE INVENTION According to this invention, it can suppress that the position of an optical member shifts | deviates.

1 is a configuration diagram of an image reading apparatus according to an embodiment of the present invention. It is an external appearance perspective view of a mirror and a holding mechanism. It is an external appearance perspective view of the holding part of a holding mechanism. It is an external appearance perspective view of the holding part of a holding mechanism. It is an external appearance perspective view of a slider unit. It is a block diagram of the image reading apparatus which the position of the mirror in the periphery of the y axis shifted. 10 is an external perspective view of a holding mechanism of an image reading apparatus described in Patent Literature 1. FIG.

  An image reading apparatus provided with a holding mechanism according to an embodiment of the present invention will be described below.

(Configuration of image reading device)
FIG. 1 is a configuration diagram of an image reading apparatus 10 according to an embodiment of the present invention. Hereinafter, the vertical direction is defined as the z-axis direction, and the moving direction of the slider units 18 and 20 (that is, the sub-scanning direction) is defined as the x-axis direction. A direction orthogonal to the x-axis direction and the z-axis direction (that is, the main scanning direction) is defined as the y-axis direction.

  As shown in FIG. 1, the image reading apparatus 10 includes a main body 12, a document cover 14, a platen glass 16, slider units 18 and 20, an imaging lens 22, and an image sensor 24.

  The main body 12 is a rectangular parallelepiped housing provided with a document cover 14, a platen glass 16, slider units 18 and 20, an imaging lens 22, and an image sensor 24. The platen glass 16 is a rectangular transparent plate attached to an opening provided on the positive side of the main body 12 in the z-axis direction. The document P is placed on the upper surface of the platen glass 16 with the reading surface facing the negative direction side in the z-axis direction.

  As shown in FIG. 1, the document cover 14 functions to bring the document P into close contact with the platen glass 16 by covering the document P.

  As shown in FIG. 1, the slider unit 18 moves toward the positive side in the x-axis direction along the original P by moving means such as a motor, a belt, and a pulley (not shown) when the original P is being read. And moved at a speed V. As shown in FIG. 1, the slider unit 18 includes a light source device 27 and a mirror 29.

  The light source device 27 irradiates the document P with light, and is configured by a combination of an LED and a light guide, for example. As shown in FIG. 1, the mirror 29 reflects the light B reflected from the original P toward the negative side in the x-axis direction (one side in the sliding direction of the slider unit 18).

  When the original P is being read, the slider unit 20 is moved along the original P toward the positive side in the x-axis direction by moving means such as a motor, a belt and a pulley (not shown) as shown in FIG. Is moved at a speed of V / 2. The slider unit 20 includes mirrors 30 and 32 and a holding mechanism (not shown in FIG. 1) described later.

  The mirror 30 reflects the light B reflected by the mirror 29 toward the negative direction side in the z-axis direction (a direction orthogonal to the sliding direction of the slider unit 18). The mirror 32 reflects the light B reflected by the mirror 30 to the positive direction side in the x-axis direction (the other side in the sliding direction of the slider unit 18).

  The imaging lens 22 forms an optical image obtained by the light B on the image sensor 24. The imaging element 24 is a light receiving element that receives the light B reflected by the mirror 32. Specifically, the imaging device 24 has a one-dimensional imaging region extending in the y-axis direction, and is a CCD camera or the like that scans an optical image formed by the imaging lens 22 and reads an image of the original P. It is a line sensor.

  In the image reading apparatus 10 configured as described above, when the original P is read, the light B emitted from the light source device 27 is applied to the original P, and the light B reflected from the original P is reflected by the mirrors 29, 30, 30. 32 are sequentially reflected. Then, the light B reflected by the mirror 32 enters the imaging lens 22 and is imaged on the image sensor 24 by the imaging lens 22. The image sensor 24 performs photoelectric conversion for each pixel according to the intensity of incident light, thereby generating an image signal (RGB signal) corresponding to the document image, and outputs the image signal to a control unit (not shown).

  Here, when the slider unit 18 is moved at the speed V and the slider unit 20 is moved at the speed V / 2, the path of the light B between the reading surface of the original P and the image sensor 24 during the movement is moved. The length is kept constant. Thereby, the light B is always coupled onto the image sensor 24 while the document P is being read.

  Incidentally, the image reading apparatus 10 is provided with a holding mechanism for suppressing the position of the mirror 32 from shifting. FIG. 2 is an external perspective view of the mirrors 30 and 32 and the holding mechanism 50. FIG. 3 is an external perspective view of the holding unit 40 of the holding mechanism 50. FIG. 4 is an external perspective view of the holding portion 42 of the holding mechanism 50. FIG. 5 is an external perspective view of the slider unit 20. In FIG. 5, the slider unit 20 is shown with the mirror 32 removed. 2 to 5, the normal direction of the mirror 32 is defined as the β-axis direction. Further, the direction orthogonal to the y-axis direction and the β-axis direction is defined as the α-axis direction. The α axis and the β axis are axes obtained by rotating the x axis and the z axis by 45 ° around the y axis, respectively.

  The holding mechanism 50 holds plate-like mirrors 30 and 32 extending in the y-axis direction, and includes holding portions 40 and 42 as shown in FIGS.

  The holding unit 40 holds the end of the mirrors 30 and 32 on the negative side in the y-axis direction, and includes a holding member 52 and elastic members 62 and 70 as shown in FIGS. 2, 3, and 5. . The holding member 52 is manufactured by bending a metal plate, and includes a main body 52a and protrusions 52b and 52c (support portions).

  The main body 52a is a plate-like member perpendicular to the y-axis direction and is perpendicular to the mirrors 30 and 32. The main body 52a is provided with recesses G1 and G2 in which a part of the outer edge of the main body 52a is recessed. As shown in FIG. 3, the concave portion G1 is formed by the side of the negative direction side of the main body 52a in the β-axis direction being recessed in a rectangular shape. As shown in FIG. 3, the concave portion G2 is formed by the side of the negative side of the main body 52a in the α-axis direction being recessed in a rectangular shape.

  The main body 52a has openings h3 and h4. The opening h3 is provided on the positive side of the recess G1 in the β-axis direction. The opening h4 is provided on the positive side in the α-axis direction of the recess G2.

  The protrusion 52b protrudes toward the negative direction side in the β-axis direction at the bottom of the recess G1. The protrusion 52c protrudes toward the negative direction side in the α-axis direction at the bottom of the recess G2.

  The holding part 42 holds the end part on the positive side in the y-axis direction of the mirrors 30 and 32, and includes a holding member 54 and elastic members 60 and 72 as shown in FIGS. 2, 4 and 5. . The holding member 54 is manufactured by bending a metal plate, and includes a main body 54a (planar member), a facing portion 54b (planar member), protrusions 54c, 54f, 54g (support portion), an adjustment screw 54d (support portion), and A stopper 54e is included.

  The main body 54a is a plate-like member perpendicular to the y-axis direction, and is perpendicular to the mirrors 30 and 32. The main body 54a is provided with a recess G3 in which a part of the outer edge of the main body 54a is recessed. As shown in FIG. 4, the recess G3 is formed by the side of the negative side of the α axis direction of the main body 54a being recessed in a rectangular shape.

  The facing portion 54b is connected to the main body 54a, and faces the main surface S1 on the positive side in the β-axis direction of the mirror 32 at the end portion on the positive direction side in the y-axis direction of the mirror 32. More specifically, the main body 54a and the facing portion 54b are formed by bending a single metal plate and are substantially perpendicular. Therefore, the facing portion 54b is substantially perpendicular to the β axis. Thereby, the facing portion 54b is parallel to the main surface S1 of the mirror 32. Further, the width of the facing portion 54b in the α-axis direction is larger than the width of the mirror 32 in the α-axis direction. Furthermore, the connection part (namely, the broken line of a metal plate) of the main body 54a and the opposing part 54b is extended in the (alpha) -axis direction.

  The main body 54a is provided with openings h1 and h2. The opening h1 is provided on the positive side in the β-axis direction of the facing portion 54b. The opening h2 is provided on the positive direction side in the α direction of the recess G3.

  As shown in FIG. 5, the protrusion 54 c protrudes from the facing portion 54 b toward the negative side in the β-axis direction. The protrusion 54c is formed by pressing the facing portion 54b. Therefore, the tip of the protrusion 54c is spherical.

  As shown in FIGS. 4 and 5, the adjustment screw 54d is a stepped screw that penetrates the facing portion 54b, and protrudes from the facing portion 54b toward the negative direction side in the β-axis direction. The adjustment screw 54d is attached to the facing portion 54b from the positive side in the β-axis direction, and is configured such that the amount of protrusion with respect to the facing portion 54b can be adjusted by rotation.

  Further, the protrusion 54c and the adjustment screw 54d are arranged in a direction intersecting the y-axis direction. In the present embodiment, the protrusion 54c and the adjustment screw 54d are arranged in the α-axis direction in the vicinity of the connection portion between the main body 54a and the facing portion 54b. The adjustment screw 54d is located on the positive direction side in the α-axis direction with respect to the protrusion 54c.

  The protrusions 54f and 54g protrude toward the negative side in the α-axis direction at the bottom of the recess G3. The protrusions 54f and 54g are provided so as to be arranged in this order from the positive direction side to the negative direction side in the β-axis direction.

  The stopper 54e protrudes from the facing portion 54b in the same direction as the adjustment screw 54d and the protrusion 54c protrude (that is, the negative direction side in the β-axis direction). In the present embodiment, the stopper 54e is connected to the facing portion 54b, and is configured by bending a single metal plate. As shown in FIG. 4, the stopper 54e is provided on the positive side in the α-axis direction with respect to the adjusting screw 54d and the protrusion 54c.

  The tips of the protrusions 52b and 54c and the tip of the adjustment screw 54d configured as described above form a plane that is substantially perpendicular to the β-axis direction. The end of the mirror 32 on the negative side in the y-axis direction is placed in the recess G1, and the end of the mirror 32 on the positive side in the y-axis direction is placed on the facing portion 54b. Accordingly, the protrusions 52b and 54c and the adjustment screw 54d are in contact with the main surface S1 on the positive side in the β-axis direction of the mirror 30 at points. As a result, the mirror 32 is positioned on a plane formed by the tips of the protrusions 52b and 54c and the tip of the adjustment screw 54d. That is, the mirror 32 is positioned around the y axis.

  Further, the negative end of the mirror 32 in the y-axis direction is positioned in the α-axis direction by the recess G1. Further, the end of the mirror 32 on the positive side in the y-axis direction is such that the stopper 54e contacts the side surface S3 (the side surface extending in the y-axis direction) of the mirror 32 on the positive side in the α-axis direction. , Is positioned in the α-axis direction. Thereby, the mirror 32 is positioned around the β axis.

  Further, the tips of the protrusions 52c, 54f, 54g form a plane substantially perpendicular to the α-axis direction. The end of the mirror 30 on the negative side in the y-axis direction is placed in the recess G2, and the end of the mirror 30 on the positive side in the y-axis direction is placed in the recess G3. Thereby, the protrusions 52c, 54f, and 54g are in contact with the main surface S4 on the positive side in the α-axis direction of the mirror 30 at points. As a result, the mirror 30 is positioned on the plane formed by the tips of the protrusions 52c, 54f, and 54g. That is, the mirror 32 is positioned around the y axis.

  Further, the negative end of the mirror 30 in the y-axis direction is positioned in the β-axis direction by the recess G2. Further, the end of the mirror 30 on the positive side in the y-axis direction is positioned in the β-axis direction by the recess G3. Thereby, the mirror 30 is positioned around the α axis.

  The elastic member 70 is produced by bending a single metal plate into a U shape. 2 and 3, one end of the elastic member 70 is inserted into the opening h4, and the other end of the elastic member 70 is positioned on the main surface S5 on the negative direction side of the mirror 30 in the α-axis direction. Accordingly, the elastic member 70 presses the mirror 30 against the protrusion 52c.

  The elastic member 72 is manufactured by bending a single metal plate into a U-shape. 2 and 4, one end of the elastic member 72 is inserted into the opening h2, and the other end of the elastic member 72 is located on the main surface S5 on the negative direction side of the mirror 30 in the α-axis direction. Accordingly, the elastic member 72 presses the mirror 30 against the protrusions 54f and 54g.

  The elastic member 60 is manufactured by bending a single metal plate into a U-shape. One end of the elastic member 60 is inserted into the opening h1, and the other end of the elastic member 60 is positioned on the main surface S2 on the negative direction side of the mirror 32 in the β-axis direction. The other end of the elastic member 60 is in contact with the main surface S2 of the mirror 32 at a contact portion located on a line parallel to the direction in which the protrusion 54c and the adjustment screw 54d are aligned (α-axis direction). Thus, the elastic member 60 presses the mirror 32 against the protrusions 52b and 54c and the adjustment screw 54d.

  The elastic member 62 is manufactured by bending a single metal plate into a U-shape. One end of the elastic member 62 is inserted into the opening h3, and the other end of the elastic member 62 is positioned on the main surface S2 on the negative side in the β-axis direction of the mirror 30. Thus, the elastic member 62 presses the mirror 32 against the protrusion 52b.

  Moreover, the holding | maintenance parts 40 and 42 and the mirrors 30 and 32 are attached to the frame 74, as shown in FIG. More specifically, the frame 74 has a rectangular frame shape when viewed in plan from the z-axis direction, and constitutes the main body of the slider unit 20. The holding portions 40 and 42 and the mirrors 30 and 32 are provided in a space surrounded by the frame body 74. That is, the slider unit 20 includes holding portions 40 and 42, mirrors 30 and 32, and a frame body 74.

(effect)
According to the holding structure 50 configured as described above, it is possible to prevent the position of the mirror 32 from shifting. More specifically, in the holding mechanism 500 described in Patent Document 1, the protrusion 505 is provided on the arm 504d. The arm 504d constitutes an L-shaped plate member together with the arm 504c. The L-shaped plate member bent in this manner is relatively easily deformed by an external force because the strength of the bent portion is weak. On the other hand, since the protrusion 504a is a part of the flat holding member 504, it is less likely to be deformed than the arm 504d.

  Therefore, when the image reading apparatus receives vibration due to conveyance or the like, the angle formed by the arm 504c and the arm 504d may change, and the position of the protrusion 505 may change. However, since the protrusion 504a is difficult to deform, the position of the protrusion 504a does not change. That is, a deviation occurs in the relative position between the protrusion 505 and the protrusion 504a. As a result, the position of the mirror 502 around the axis Ax may be shifted.

  Therefore, in the holding structure 50, the facing portion 54 b faces the main surface S <b> 1 of the mirror 32 at the end portion on the positive side in the y-axis direction of the mirror 32. Further, the protrusion 54c and the adjustment screw 54d protrude from the facing portion 54b and are in contact with the main surface S1 of the mirror 32. That is, the protrusion 54c and the adjustment screw 54d are provided on the same member (opposing portion 54b). Therefore, when the facing portion 54b is inclined due to vibration or the like during conveyance of the image reading apparatus 10, the positions of both the protrusion 54c and the adjustment screw 54d are shifted. That is, no deviation occurs in the relative position between the protrusion 54c and the adjustment screw 54d. As a result, the position of the mirror 32 around the y axis is prevented from shifting.

  In the holding structure 50, the protrusion 54c and the adjustment screw 54d are arranged in the α-axis direction. Further, the connecting portion between the main body 54a and the facing portion 54b extends in the α-axis direction. As a result, when the facing portion 54b is inclined, the magnitude of the positional deviation of the projection 54c in the y-axis direction and the β-axis direction and the magnitude of the positional deviation of the adjustment screw 54d in the y-axis direction and the β-axis direction become equal. As a result, the position of the mirror 32 around the y axis is more effectively suppressed. Furthermore, the mirror 32 is suppressed from being twisted.

  Here, if the position of the mirror 32 around the y-axis is suppressed from shifting, the image quality is improved. FIG. 6 is a configuration diagram of the image reading apparatus 10 ′ in which the position of the mirror 32 around the y-axis is shifted. 6A, the end of the original P on the positive side in the x-axis direction (hereinafter simply referred to as the rear end of the original P) is read. In FIG. 6B, the x-axis of the original P is read. The negative end of the direction (hereinafter simply referred to as the leading edge of the document P) is read.

  If the position of the mirror 32 around the y-axis is shifted, the relative position between the reading position P1 and the light source device 27 at the rear end of the original P shown in FIG. 6A and the front end of the original P shown in FIG. There is a deviation between the reading position P2 and the relative position of the light source device 27. More specifically, the light beams B1 and B2 reflected at the reading positions P1 and P2 of the document P need to be reflected at the position p2 of the mirror 30 and the position p3 of the mirror 32 in order to enter the image sensor 24. Here, the distance between the slider units 18 and 20 when the trailing edge of the document P is read is larger than the distance between the slider units 18 and 20 when the leading edge of the document P is read. Further, the lights B1 and B2 traveling between the mirrors 29 and 30 are inclined with respect to the x-axis direction. Therefore, the position p1 where the light B1 is reflected by the mirror 29 and the position p4 where the light B2 is reflected by the mirror 29 are different. As a result, a deviation occurs between the relative position between the reading position P1 and the light source device 27 at the trailing edge of the document P and the relative position between the reading position P2 and the light source device 27 at the leading edge of the document P. Such a relative position shift is called a line-of-sight shift.

  Here, the light emitted from the light source device 27 has a light distribution in the x-axis direction. Therefore, the intensity of the light that irradiates the reading position P1 is different from the intensity of the light that irradiates the reading position P2. Therefore, there is a difference between the image brightness at the leading edge of the document P and the image brightness at the trailing edge of the document P. As described above, if the position of the mirror 32 around the y-axis is shifted, the brightness of the image of the original P is uneven, and the image quality is deteriorated.

  Therefore, the image reading apparatus 10 includes a holding structure 50. Thereby, it is suppressed that the position of the mirror 32 around the y-axis is shifted. As a result, in the image reading apparatus 10, the occurrence of line-of-sight shift is suppressed, and the image quality is improved.

  Here, in the image reading apparatus 10, the light source used for the light source device 27 may be an LED or a fluorescent lamp, but is preferably an LED. The directivity of the LED is stronger than the directivity of the fluorescent lamp. Therefore, when the LED is used as the light source, the difference between the intensity of the light that irradiates the reading position P1 and the intensity of the light that irradiates the reading position P2 irradiates the reading position P1 when a fluorescent lamp is used as the light source. It becomes larger than the difference between the intensity of light to be emitted and the intensity of light to irradiate the reading position P2. Therefore, the image reading apparatus 10 in which the LED is used as the light source has a remarkable improvement in the image quality by applying the holding structure 50 to the image reading apparatus 10 in which the fluorescent light is used as the light source. appear. Further, since the power consumption of the LED is less than the power consumption of the fluorescent lamp, the power consumption of the image reading apparatus 10 can be reduced by using the LED as the light source.

  In the holding structure 50, when the facing portion 54b is tilted, the mirror 32 may be tilted with respect to the y-axis direction. However, the length of the mirror 32 in the y-axis direction is sufficiently long. Therefore, since the magnitude of the angle at which the mirror 32 tilts with respect to the y-axis direction is extremely small, the degradation in image quality is extremely small.

  Further, when the projection 54c and the adjustment screw 54d are provided in the vicinity of the connecting portion between the main body 54a and the facing portion 54b, even if the facing portion 54b is inclined, the positional deviation in the β-axis direction of the projection 54c and the adjustment screw 54d is small. I'm sorry. As a result, the mirror 32 is prevented from tilting with respect to the y-axis.

  The other end of the elastic member 60 is in contact with the main surface S2 of the mirror 32 at a contact portion extending in a direction (α-axis direction) parallel to the direction in which the protrusions 54c and the adjustment screw 54d are arranged. Thereby, it is suppressed that the mirror 32 is twisted.

  Further, the width of the facing portion 54b in the α-axis direction is larger than the width of the mirror 32 in the α-axis direction. Thereby, the space | interval of the processus | protrusion 54c and the adjustment screw 54d can be enlarged. As a result, the mirror 32 can be stably supported by the protrusions 52b and 54c and the adjusting screw 54d. Further, when the distance between the protrusion 54c and the adjustment screw 54d is increased, the change in the position of the mirror 32 around the y-axis is reduced with respect to the change in the protrusion amount of the adjustment screw 54d with respect to the facing portion 54b. As a result, it becomes easy to finely adjust the position of the mirror 32 around the y-axis with the adjusting screw 54d.

  The facing portion 54b and the stopper 54e are manufactured by bending a single metal plate. That is, the stopper 54e is not made of a member different from the facing portion 54b. Thereby, the intensity | strength of the stopper 54e can be improved compared with the structure which produced these with another member. Further, the stopper 54e is formed by being bent from the surface of the metal plate constituting the facing portion 54b. Accordingly, the width of the facing portion 54b in the y-axis direction can be increased without excessively expanding the developed length of the metal plate, and the strength of the facing portion 54b can be improved. More specifically, a case where a counter part having the same length in the y-axis direction as that of the counter part 54b is produced by separately bending and forming the stopper and the counter part from a single metal plate. Therefore, it is necessary to take a wider development area of the metal plate. Further, when the stopper and the facing portion are separately bent from a single metal plate without changing the development area of the metal plate, the facing portion is shortened due to the development of the metal plate. For this reason, the stopper 54e is formed by being bent from the surface of the metal plate that constitutes the facing portion 54b.

  In the holding mechanism 50, the adjustment screw 54d is constituted by a step screw. Accordingly, by designing the elastic member 60 so that it does not undergo plastic deformation when the adjustment screw 54d is fitted to the stepped portion, plastic deformation of the elastic member 60 due to excessive tightening of the adjustment screw 54d can be suppressed. As a result, the mirror 32 is held by the holding unit 42 with an appropriate force.

  In addition, as a configuration in which the angle of the mirror 32 can be adjusted, the adjusting screw 54d is not limited to be disposed on the upper side of the mirror 32, but may be disposed on the lower side of the mirror 32. Further, the holding mechanism 50 is not limited to being provided in the slider unit 20, and may be provided in the slider unit 18, for example. By using the holding mechanism according to the present invention to hold the mirror provided in the optical path between the light source and the image pickup device, it is possible to suppress the positional deviation of the mirror due to vibration or the like accompanying the image reading operation.

  As described above, the present invention is useful for the holding mechanism and the image reading apparatus, and is excellent in that the position of the optical member can be prevented from shifting.

DESCRIPTION OF SYMBOLS 10 Image reader 12 Main body 18, 20 Slider unit 22 Imaging lens 24 Imaging element 27 Light source device 29, 30, 32 Mirror 40, 42 Holding part 50 Holding mechanism 52, 54 Holding member 52a, 54a Main body 52b, 52c, 54c, 54f, 54g Projection 54b Opposing part 54d Adjustment screw 54e Stopper 60, 62, 70, 72 Elastic member

Claims (10)

A holding mechanism for holding a plate-like optical element extending in a predetermined direction,
A first holding unit for holding one end of the optical element in the predetermined direction;
A second holding portion for holding the other end portion of the optical element in the predetermined direction;
With
The second holding part is
A first planar member facing one main surface of the optical element at the other end of the optical element;
A first support that protrudes from the first planar member and contacts the one main surface of the optical element;
A second support portion that protrudes from the first planar member and contacts the one main surface of the optical element, and is configured to be capable of adjusting a protruding amount with respect to the first planar member. A second support,
Including
A holding mechanism characterized by. The first support part and the second support part are arranged in a direction crossing the predetermined direction;
The holding mechanism according to claim 1. The first holding part is
A third support portion in contact with one main surface of the optical element;
Including
The holding mechanism according to any one of claims 1 and 2. The second holding part is
A first urging member that presses the optical element against the first support portion and the second support portion, and in which the first support portion and the second support portion are arranged side by side A first biasing member in contact with the optical element at a contact portion located on a line parallel to
Including further,
The holding mechanism according to any one of claims 1 to 3, wherein: The first holding part is
A second urging member that presses the optical element against the third support portion;
Including further,
The holding mechanism according to claim 3. The first planar member is connected to a second planar member substantially orthogonal to the main surface of the optical element;
The holding mechanism according to claim 1, wherein: The width of the first planar member in the direction orthogonal to the predetermined direction is larger than the width of the optical element in the direction orthogonal to the predetermined direction;
The holding mechanism according to any one of claims 1 to 6. The second holding part is
A stopper that protrudes from the first planar member in the same direction as the first support portion and the second support portion protrude from the first planar member and extends in a predetermined direction in the optical element; The stopper that contacts the side
Including further,
A holding mechanism according to any one of claims 1 to 7. The optical element is a mirror;
The holding mechanism according to any one of claims 1 to 8. An image reading device for reading a document,
A first unit that slides along the document, a light source that irradiates the document with light and a first mirror that reflects light reflected by the document to one side in the sliding direction of the first unit; A first unit comprising:
A second unit that slides along the document, wherein the second mirror reflects light reflected by the first mirror in a direction perpendicular to the sliding direction; and slides light reflected by the second mirror. A third mirror that reflects to the other side of the direction, and a second unit that includes the holding mechanism according to claim 9 that holds the third mirror;
An image sensor for receiving the light reflected by the third mirror;
Having
An image reading apparatus characterized by the above.

Images